1. Field of the Invention
The present invention relates to a method and apparatus for manufacturing electronic parts. More particularly, the present invention relates to a method and apparatus for manufacturing electronic parts in which wiring boards on which a plurality of IC chips are mounted and which are packaged by means of a synthetic resin are cut in order to cut these boards into individual IC packages.
2. Description of the Related Art
As semiconductors have become more highly integrated, packages in which the leads are disposed on the undersurface of the package as in a BGA (ball grid array) or the like have begun to be used. The manufacture of individual IC packages by the cutting of a wiring board on which IC chips sealed with a synthetic resin are mounted is known. Various methods have been proposed as methods for cutting IC chips packaged in a synthetic resin into individual IC packages. The separation of IC packages on which IC chips are mounted by cutting using a diamond saw (which is a cutting grindstone using a diamond blade) or the like is one example of such a method.
Furthermore, prior to the dicing of semiconductor substrates, measures such as coating of the back surfaces of the semiconductor substrates with a polyimide and bonding to a dicing tape or the like are performed. Moreover, cutting in a cross pattern using the same cutting device with the orientation of the table on which the semiconductor substrates are carried being varied is also known as a separation method. Furthermore, in such separation processes, tape bonding is performed prior to cutting, and cleaning using a cleaning liquid is performed following cutting in order to remove adhering cutting debris.
However, conventional separation methods involve various problems, and it has not always been possible to increase the production efficiency. In regard to tape bonding, the following problem has been encountered: specifically, in cases where cutting is performed with the tape in a bonded state, the grindstone may become clogged during cutting so that operation becomes impossible, thus resulting in defective products.
Furthermore, since cleaning following cutting is performed using wash water, there is a danger of the dissolution of heavy metals, so that a special waste water treatment must be performed in order to avoid environmental problems; as a result, the cost of the product is increased. Since water is used for cleaning, this water invades fine cracks and peeled areas in stacked parts, and remains in these areas. As a result, there is a danger that these parts will become corroded, or that current leakage will occur so that a defective product is produced.
The abovementioned cutting is performed by the same cutting device while indexing the table on which the member that is being cut, such as a wiring board or the like, is carried, and varying the direction so that cutting is performed again in a different direction. Simultaneous cutting in two directions cannot be performed using a single working apparatus. Furthermore, in the case of mass production, a line is constructed, and the work is divided into a plurality of processes. However, this results in the use of lines that are used exclusively for specified products that are being worked, so that such a method lacks flexibility; furthermore, such a process is expensive and requires a large amount of space for the equipment.
Especially in cases where there is a change in the member that is being cut, such as a wiring board or the like, expensive jigs and tools must be changed; furthermore, a degree of experience in the working process is also required, and time is required for such replacements. Also in cases where the finished products are recovered and accommodated, conventional methods involve a process in which the solder ball parts, which consist of metallic solder and which are connected to printed circuit boards, are caused to face the cutting tool during cutting. In other words, cutting is ordinarily performed with the solder ball parts facing upward. Accordingly, after cutting or when the products are recovered, the products are again inverted and accommodated in a case with the solder ball parts facing downward. Consequently, time is also required for this accommodation of the products.
The present invention was devised on the basis of such a technical background, and achieves the following objects.
One object of the present invention is to provide a method and apparatus for manufacturing electronic parts which are devised so that different wiring boards can be simultaneously cut by a plurality of cutting devices, thus improving the manufacturing efficiency in economic terms.
A further object of the present invention is to provide a method and apparatus for manufacturing electronic parts which are devised so that dust generated in the cutting step is captured in order to protect the electronic parts during cutting, thus improving the quality of the electronic parts.
A further object of the present invention is to provide a method and apparatus for manufacturing electronic parts in which the positions of the conveyed wiring boards are accurately recognized so that cutting is performed in accurate cutting positions, thus increasing the cutting efficiency.
A further object of the present invention is to provide a method and apparatus for manufacturing electronic parts which are devised so that the electronic parts that have been cut are cleaned and inverted in the product accommodating step, thus allowing efficient product accommodation in a short period of time.
The present invention adopts the following means in order to achieve the abovementioned objects.
The method of the present invention for manufacturing electronic parts comprises a conveying step wherein plate-form electronic parts sealed in resin are conveyed, a first fastening step wherein said conveyed plate-form electronic parts are positioned and fastened in place, a first cutting step wherein said plate-form electronic parts that have been positioned and fastened in place in said first fastening step are moved in one direction on the plane including said electronic parts, and are cut, a second fastening step wherein strip-form electronic parts that have been cut in said first cutting step are conveyed, positioned and fastened in place, a second cutting step wherein the strip-form electronic parts that have been conveyed, positioned and fastened in place in said second fastening step are moved in a direction that crosses the abovementioned cutting direction, and are cut, and a product accommodating step wherein single electronic parts that have been cut in said second cutting step are accommodated.
Furthermore, said first fastening step and said second fastening step may include an optical recognition step wherein the positions of said plate-form electronic parts or said strip-form electronic parts that are conveyed are optically recognized.
Furthermore, said first fastening step and said second fastening step may be press-fastening steps wherein said plate-form electronic parts or said strip-form electronic parts are fastened in place by the application of pressure from above after said electronic parts have been placed on a carrying table.
Furthermore, said first cutting step and second cutting step may be steps wherein cutting is performed by causing a rotary grindstone to move.
Furthermore, said first cutting step and second cutting step may include a step wherein dust or the like generated by cutting is removed by suction.
Furthermore, said product accommodating step may include a step wherein said single electronic parts cut in said second cutting step are clamped and inverted, and the orientation of said electronic parts is altered.
Furthermore, said product accommodating step may include a step wherein said clamped single electronic parts are brushed.
The apparatus of the present invention for manufacturing electronic parts comprises a conveying body which is used to convey the electronic parts, a first fastening device which positions and fastens plate-form electronic parts sealed in resin that are conveyed by said conveying body, a first cutting device which moves said electronic parts that have been positioned and fastened in place by said first fastening device in one direction on the plane including said electronic parts, and cuts said electronic parts, a second fastening device which conveys, positions and fastens strip-form electronic parts that have been cut by said first cutting device, a second cutting device which moves said strip-form electronic parts that have been conveyed, positioned and fastened in place by said second fastening device in a direction that crosses the abovementioned cutting direction, and which cuts said electronic parts, and a product accommodating device which accommodates the single electronic parts that have been cut by said second cutting device.
Furthermore, the first fastening device and said second fastening device may contain a position recognition device which optically recognizes the positions of said plate-form electronic parts or said strip-form electronic parts that have been conveyed.
Furthermore, the device that optically recognizes the positions of said plate-form electronic parts or said strip-form electronic parts may be a device which recognizes the shapes of said electronic parts by means of a CCD camera, and specifies the cutting positions.
Furthermore, the first fastening device and said second fastening device may be devices that fasten said conveyed plate-form electronic parts or said [conveyed] strip-form electronic parts by means of restraining members that apply pressure from above after said electronic parts have been placed on a carrying table.
Furthermore, said first fastening device and said second fastening device may be devices that have attached means fastening said plate-form electronic parts or said strip-form electronic parts by means of a vacuum suction force.
Furthermore, in said first fastening device and said second fastening device, projecting parts which are used to press said plate-form electronic parts or said strip-form electronic parts may be formed on said restraining member.
Furthermore, in the restraining members that fasten said plate-form electronic parts or said strip-form electronic parts after said electronic parts have been placed on a carrying table, cutting grooves which are used to allow the passage of a rotary tool in order to cut said plate-form electronic parts or said strip-form electronic parts may be formed in said carrying tables and restraining members.
Furthermore, said first cutting device and second cutting device may be equipped with dust collectors that use suction to capture the dust-form cutting debris that is generated by cutting.
Furthermore, said first cutting device and said second cutting device may be devices which have rotary cutting tools, and which perform advancing and retracting movements on two or more axes.
Furthermore, said rotary cutting tools may be tools that are formed as composite tools by the electrodeposition of diamond abrasive grains and CBN abrasive grains.
Furthermore, said product accommodating device may include a device which clamps said single electronic parts cut by said second cutting device, inverts said electronic parts and alters the orientation of said electronic parts.
Furthermore, said product accommodating device may include a device which brushes the clamped single electronic parts.